car died twice whild driving,first time was ok when went back to car 10 mins later, had left headlites on & it started right up–totally dead next morn,after continued trying to start, first got rapid clicking/buzzing under pass dash (ecm?)then lites came on briefly then everything lit up & it started has done this twice in last week, never any probs till was in shop first for heater core then for inspection–horn wouldn’t work installed new relay still wouldn’t work other mech stuck a direct horn button on dash, could any of these elec related repairs affect the ecm?